Adaptive Modulation Control for Multiple-Phase Voltage Regulators

Abstract

This letter presents an adaptive modulation control (AMC) method which has proven to be effective in achieving high bandwidth designs as well as stabilizing the control loop during large load transients. The AMC adaptively adjusts control bandwidth by changing the modulation gain, depending on different load conditions. With the AMC, a multiphase voltage regulator can be designed with an aggressively high bandwidth, while in heavy load transients where the loop could be potentially unstable, the bandwidth is lowered. Therefore, the AMC provides an optimal means for robust high-bandwidth design with excellent transient performance. It is a type of non-linear control designed for, but not limited to, multiphase voltage regulators with droop control. Detailed analysis of the operational mechanism is presented. Experiment results are included to verify the analysis.